R'hllor

R'hllor, also known as the Red God and the Lord of Light is the predominant deity in Essos, and several of its cities are home to grand temples in his honor. Yet in Westeros, he is still a foreign concept, and thus he and the faith's rituals are viewed with suspicion, as are its converts. Defenders of the Lord of Light are known as Red Priests because of the crimson robes they wear; their symbol is a fiery heart. Red Priests sing prayers each night beseeching the Lord of Light to bring back the dawn: "The night is dark and full of terrors." Shadows are important too, as they are created by light. His antithesis is a being known as the Great Other.